Transmitter-mouthpiece.



4W @7%. N @a w. W.l DEAN. TRANSMITTER MOUTHPIEGE.

' APPLICATION FILED 00T. 8, 1908.

927,643. Patented Ju1y13,1a99.

wr/066.565,' 4 lZzzjztar' UNITED STATES PATENT OFFICE.

WILLIAM W. DEAN, OF ELYRIA., OHIO, ASSIGNOR TO THE DEAN ELECTRICCOMPANY, OF

ELYRIA, OHIO, A CORPORATION OF OHIO,

TnANsmTTEn-MoUTH-PIECE.

To all whom it may concern:

Be it known that I, l/VILLIAM W. DEAN, a citizen of the United States,residing at Elyria, in the county of Lorain and State of Ohio, haveinvented a certain new and useful Improvement in Transmitter-Mouthpieces, of which the following is a full, clear, concise, and exactdescription, reference being had to the accompanying drawings, formin apart of this specification.

In t e .past mouthpieces for telephone transmitters have commonly been'made of insulating material of one form or another, and since they havegenerally been constructed of non-metallic material there has been alarge amount of difficulty attending their use as a result of breakage.Furthermore, mouthpieces of this class are comparatively expensive andit is an object of this invention to eliminate these difficulties by theconstruction of a metallic mouthiece adapted to be formed from sheetmetal lly means of dies. In connection with forming my improvedmouthpiece of Sheet metal several im ortant advantages result which willbe exp ained below` The several drawings illustrating my invention areas follows:

Figure l is a side View of my improved mouthpiece in position in atransmitter casing. Fig. 2 isfa rear end view of the mouthpiece; andFig. 3 is a longitudinal sectional View taken through the center of themouthpiece.

Similar reference characters refer to similar )arts throughout theseveral views.

'.llie transmitter mouthpiece A, as shown in Fig. 1, consists of abell-shaped body portion l so formed that its smaller end `is ofsomewhat less diameter than the portion of the body of the mouth ieeeadjacent thereto, these two ortions )eing separated by a shoulder 2.Vlhe smaller end portion has threads 3 formed `on its outer surface. Theend of' this smaller portion is closed byl an integral wall 4',l inwhich perforations 5 are made. The threaded portion 3 is adapted to enage and cooperate with an internally threacgle'd flange formed on thefront plate 6 of the transmitter casingB, The shoulder 2 is adaptedto'bear against the outer end of the flange formed on the front plate 6.In constructing my mouthpiece a circular blank of sheet metal is firstpunched out and this Specilcation of Letters Patent.

Applieationled October 8, 1908.

Patented July 13, 1909.

Serial No. 456,759.

is then drawn into the sha e shown in vthe drawings by means of suita leforming dies. After having been thus formed the outer edge of thebell-shaped portion is rounded to remove the sharp edges and the threads3 are formed on the smaller end. The perforations 5 are formed in theend wall of the mouthpiece after it has been formed, and theseperforationsmay be made eitherby punching ordrilling as desired. The"mouthpiece isthencoated with a protecting enamel, as japan, which servesto protect it from corrosion by the moisture in the atmosphere or bymoisture precipitated from the breath of the user, and in thisconnection it is to be noted thatl it is very advantageous to have theWall 4 at the extreme end of the mouthpiece in order that all of themoisture thus precipitated may drain from the mouthpiece and that noneof it may collect and do damage back of the perforated Wall within thetransmitter easing. In transmitter mouth ieces as heretofore constructeda perforate Wall has generally been used, located a short distance fromthe smaller end of the mouthpiece, thus leaving .a section of themouthpiece Within the perforated Wall that it is impossible to clean andwhich readily .collects moisture and foreign particles that may be inthe atmosphere.

It is to be noted that by constructing telephone transmitter mouthpiecesas described above, comparatively thin material may be used, whileheretofore in order to get requi site strength it has been necessary tomake these mouthpieces relatively thick, the` re-v sult being that theypresented a clumsy and inartistic appearance. Furthermore, in many casesthe vsurface of the material used could not be polished so as to)reclude the possibility of foreign matter lodging upon such surface andbeing retained thereby unless considerable effort were expended to cleanthe same. coating covering the metal furnishes an ideally clean surfacereadily permitting the removal of any dust, dirt or oreign matter thatmay accumulate thereon.

l/Vhile any sheet metal ada ted to be, Worked by forming dies may e usedin forming these mouthpieces, I have fo'unil that sheet steel answersthe purpose admirably, since it is both inexpensive and strong.Furthermore, the enamel coating com- In my mouthpiece the enamel pletelyprotects the steel so that it is not corroded or attacked by moisture orfumes that ay be in the atmosphere.

W rile I have shown my invention in the particular form disclosed, I donot, however, limit myself to this exact conformation, but desire toclaim any e uivalent form that may be deemed desir-ab e by those skilledin the art.v

What I claim is:

A telephone transmitter mouthpiece consistin'gv in a bell-shaped bodyportion stamped and formed from sheetsteel, the smaller end of the bodyportion having a formed shoulder whereby the smaller end is oi smallerdiameter than the part of the mouthpiece ad- WILLIAM W. DEA N.

I'Vitnesses:

A. l). T. LIBBY, N. B. MANsoN.

